This invention relates to tool-handle holders that are positioned on a forearm and grasped by a hand of a user for single-handed operation of tools with two-hand handles.
Two-handed instead of single-handed use of hand rakes, brooms, pruning tools, pitchforks, handled nets, dustpans, power saws, swords, probing poles, protective staffs, canes, crutches, fishing poles, boat oars, scraping tools, hand-planting tools, guns and various other hand-held tools and instruments has been required previously. Single-handed operation and manipulation has been nearly impossible or extremely ineffective at best previously. With this invention, however, single-handed use is better than two-handed use has been for most of these tools and instruments. Single-handed use is now more effective, more accurate, faster and less tiring. In addition, conventional two-handed operation and manipulation of such tools and instruments has required bending and positioning of a user's body that can be unnecessarily burdensome, tiring, painful and obstructive of use-effectiveness.
Two-handed use of most such tools and instruments is not possible with a practical level of effectiveness for most of humanity due to different muscle capacity developed from normal activity than required for designed two-handed uses of such tools and instruments. Further yet, bodily injury, stiffness of bodily joints, agility, age, ability to bend one's body, insufficient back strength and other bodily conditions prevent or greatly hinder much of even the most capable people from effective two-handed use of such tools and instruments. Still further, freeing one hand and arm of a user to aid single-handed use and to achieve related objectives with the other hand and arm of the user is not possible with conventional two-hand handles.
Attempts have been made previously to solve some of these problems. Included has been an implement holder taught by Maguire in U.S. Pat. No. 2,482,589. The Maguire device taught a handle extended radially from the holder such that the handle was held and operated perpendicularly to a load on a tool or instrument attached to the holder. This had several fatal defects. For lifting, a load resistance was in line with the handle, such that a user's hand was required to grasp the handle tightly enough with sufficient work load to prevent the handle from slipping out of the user's hand in addition to applying work load for lifting. With the Maguire device, pivotal direction of a user's arm for side-sweeping action and for lifting action required that the handle be held perpendicularly to load resistance, such that bending moment or side-pressure torque was transmitted by the load to the hand. The side-pressure torque required work load in addition to work load for side-sweeping action and for arm-grasping action with tools and instruments. These additional work-load factors most often required more motive ability, muscle power and work, resulting in higher fatigue rate than for intended work with the tools and instruments. In addition to not applying physics of human-use effectiveness for handling tools and instruments, the Maguire device also required two clamps and a wire body that are structurally different from this invention.
U.S. Pat. No. 4,477,114 granted to Callis described a rake handle that was attachable to an arm of a user. But it had much of the same physical limitations of the Maguire device and was limited to use on only a rake handle instead of being attachable to a wide variety of tools and instruments.
U.S. Pat. No. 4,888,846 granted to Natale taught an asbestos-scraping assembly with which a handle of a scraper was attachable to a forearm of a user. It was effective for its limited use. But it was not as effective as attaching a scraper handle to the holding mechanism of this invention because it positioned the scraper where knuckles of a user were endangered when positioning the scraper for effective scraping action. Further, it did not allow side-sweep action in addition to forward-thrust action as made possible with this invention.
U.S. Pat. No. 4,822,087 granted to DeCarlo taught a lift-improvement device that had the exact limitations as the Maguire device but with an additional problem of not being attachable to a forearm of an individual. The physics of lifting with the human body were not addressed effectively in this or in other prior devices.